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Title: Integrating historical biogeography and environmental niche evolution to understand the geographic distribution of Datureae
Premise

The distributions of plant clades are shaped by abiotic and biotic factors as well as historical aspects such as center of origin. Dispersals between distant areas may lead to niche evolution when lineages are established in new environments. Alternatively, dispersing lineages may exhibit niche conservatism, moving between areas with similar environmental conditions. Here we test these contrasting hypotheses in the Datureae clade (Solanaceae).

Methods

We used maximum likelihood methods to estimate the ancestral range of Datureae along with the history of biogeographic events. We then characterized the niche of each taxon using climatic and soil variables and tested for shifts in environmental niche optima. Finally, we examined how these shifts relate to the niche breadth of taxa and clades within Datureae and the degree of overlap between them.

Results

Datureae originated in the Andes and subsequently expanded its range to North America and non‐Andean regions of South America. The ancestral niche, and that of mostDaturaandTrompettiaspecies, is dry, whileBrugmansiaspecies likely shifted toward a more mesic environment. Nonetheless, most Datureae present moderate to high overlap in niche breadth today.

Conclusions

The expansion of Datureae into North America was associated with niche conservatism, with dispersal into similarly dry areas as occupied by the ancestral lineage. Subsequent niche evolution, including the apparent shift to a mesic niche inBrugmansia, diversified the range of habitats occupied by species in the tribe Datureae but also led to significant niche overlap among the three genera.

 
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Award ID(s):
1413855
NSF-PAR ID:
10371232
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
American Journal of Botany
Volume:
106
Issue:
5
ISSN:
0002-9122
Page Range / eLocation ID:
p. 667-678
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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